Pop Larkin, who makes a fortune from scrap-iron deals but has never paid income tax, lives in rural idyllic bliss with generous-hearted Ma and their six children. When a young, earn'st tax official, Mr Charlton, turns up one hot May afternoon in 1957 to investigate he is bewitched immediately by eldest daughter Mariette and it isn't long before he succumbs to the boisterous Larkin family charm and largesse.